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<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style>
*{margin:0;padding:0;}

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<body>
	<div id="myDiv"></div>
    <script>
    	var div=document.getElementById('myDiv');
		
		console.log(div.tagName);//DIV
		
		console.log(div.tagName == div.nodeName);//true;
		console.log(div.nodeType);//1
		console.log(div.nodeValue);//null
		
		if(div.tagName.toLowerCase() == 'div'){
				
		}
		
		
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</body>
</html>
